Tourists in Canada are for the most part allowed to stay for 6 months unless they apply to extend their status.
If you are a Canadian citizen or PR and you apply to sponsor her for PR, inland, you can apply for an open work permit at the same time. This would give her implied status. From what I hear, open work permits are being granted in about 5 months. She would actually not have to leave. The downside of inland however is that it would not be advisable to leave again during the processing and it would take a couple of years for her to actually get PR.
It would be a good option if you want to be together and it is not important for her to be able to travel.